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  • 1
    ISSN: 0887-6258
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 7 (1963), S. 1063-1081 
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The curing reaction of an epoxy resin and acid anhydride with an amine and/or alcohol was studied kinetically. No etherification reaction occurred at 70-140°C. and the initial reaction rate was proportional to the concentration of epoxide, acid anhydride, and catalyst (tertiary amine or alcohol). The apparent activation energies of the reaction in two systems of epoxy resin-hexahydrophthalic anhydride/triethanolamine (0.5 wt. %) were obtained as 14.1 and 14.4 kcal./mole. The effects of the substitution R of the tertiary amine NR3 or alcohol R3COH as catalyst on the curing reaction of the epoxy resin and acid anhydride were studied. The polar reaction constant ρp for amines, obtained negatively, indicates that electron-repelling substituents of NR3 increase the curing rate; ρp for alcohols, obtained positively, indicates that electron-withdrawing substituents of R3COH increase the rate of curing reaction. These results supported the proposed curing mechanism better.
    Additional Material: 19 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 7 (1963), S. 1951-1973 
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Equations are derived by means of Flory's original method for the gelation point of epoxy resin/acid anhydride/polyhydric alcohol systems containing various epoxy resins, acid anhydrides, and polyhydric alcohols. The resultant equations take no account of the reactivities of the various carboxyl, epoxy, and hydroxyl groups and are applied satisfactorily to epoxy resin/acid anhydride/polyhydric alcohol systems. The difference between the observed and calculated gelation point is about 2-3% when the acid anhydride used in HHPA and 4-5% when the acid anhydride used is tri- or tetrafunctional, such as TMA and PMDA. There is a little difference between resins E-828 and E-1001 for the gelation point. The discrepancy is beleived to be due to the reactivity difference between epoxide and hydroxyl to carboxyl groups and to the occurrence of intramolecular condensation, and it is contended that the degree of intramolecular condensation in these branching systems obtained is a function of the branch unit functionality of reactant, in this case, acid anhydride or epoxide.
    Additional Material: 17 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 11 (1967), S. 1345-1358 
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Some polybasic acid derivatives were obtained from substituted benzoic acids such as p- and o-toluic acids, and p-formaldehyde in concentrated sulfuric acid by a method similar to that of Naokawa et al. The structure of these resinous substituted benzoic acid-formaldehyde materials was determined by a paper chromatography and infrared spectrum analysis, and found to be where n = 0-2; R = H, R′, and R″ = H or CH3, respectively. New glycidyl-ester-type epoxy resins were prepared from these substituted benzoic acid-formaldehyde resins and epichlorohydrin in the presence of sodium hydroxide, using dioxane as a solvent. These resins were considered to have the general structure shown above, where n = 0-2, , and R′ and R″ = H or CH3, respectively.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Hoboken, NJ : Wiley-Blackwell
    Journal of Biomedical Materials Research 20 (1986), S. 247-259 
    ISSN: 0021-9304
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: Surface characteristics of protein-treated dialdehydestarch (DAS), which is utilizable as a gastrointestinal sorbent for the treatment of uremia, are examined by scanning electron microscopy (SEM). Unique wrinkles or continuous depressions were observed on the surface of some albumin-treated DAS particles. An increase in concentration and composition of albumin to DAS produces more particles with this kind of rugged surface. On the other hand, gelatin treatment provided a DAS with somewhat rough surface. As the stoichiometric ratio of gelatin to DAS increases, some fibrous or thin-leaves-like projections became outstanding on the surface. Urea-binding properties of protein-treated DAS are just about the same regardless of the protein concentration or composition. In addition, wrinkles or depressions partly observed on the surface of albumin-treated DAS are of little benefit in terms of effective urea binding. These results mean that inherent physical properties of DAS such as dialdehyde content would be a critical factor in urea-sorption ability, rather than surface characteristic or the presence of protein.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 152 (1972), S. 217-231 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Reaktion von di- und trifunktionellen Epoxiden mit Seidenfibroin wurde in Gegenwart verschiedener Salze in mehreren Lösungsmitteln bei 45 bis 75°C untersucht. Die Reaktionsgeschwindigkeiten hängen von der Art der verwendeten Salze und Lösungsmittel ab. Große Gewichtszunahmen (bis zu 28%) wurden bei der Reaktion mit Äthylenglykol-diglycidäther, Glycerin-triglycidäther und Vinylcyclohexan-dioxid in Lösungsmitteln wie Tetrachlorkohlenstoff, Toluol, Äthanol und Isopropanol erhalten, wenn mit Thiosulfat-, Rhodanid-, Cyanid- oder Chlorionen katalysiert wurde. Die Gewichtszunahmen bei der Seide/Epoxid-Reaktion wurden hauptsächlich durch Reaktion des Epoxids mit der phenolischen Hydroxylgruppe der Tyrosinreste erhalten, wobei auch Lysin-, Histidin-, Arginin- und Serinreste reagieren. Die Seide besaß nach der Reaktion mit den Epoxiden geringe Löslichkeit in wäßriger NaOH und HCl ohne Abnahme der Feuchtigkeitsaufnahme und Biegsamkeit und hatte stark verbesserte Knitterfestigkeit.
    Notes: The reaction of di- and tri-functional epoxides with silk fibroin was investigated in the presence of various salts in different solvents at 45-75°C. The reaction rates depend on the nature of the salts and the solvents used. Large weight gains (to 28%) were obtained in the reactions with ethyleneglycol diglycidyl ether, glycerol triglycidyl ether, and vinylcyclohexene dioxide catalyzed by thiosulfate, thiocyanate, cyanide, or chloride ions in such solvents as carbon tetrachloride, toluene, ethanol, and isopropanol. The weight gains in the silk/epoxide reaction were obtained mainly by the reaction of epoxide with the phenolic hydroxyl groups of the tyrosine residues, although lysine, histidine, arginine, and serine residues were found to react. The silk fabrics reacted with the epoxides were imparted with low solubilities in aqueous NaOH and HCl solutions without an appreciable decrease of moisture regain and flexibility of the fabric, and had much improved creaseproof properties.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 64 (1977), S. 1-18 
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die heterogene Addition Zahlreicher Monoepoxyverbindungen an einigen Arten von Seidenfibroinen, wiez. B. aus Diethyoploca japonica, Antheraeapernyi, Philosamia cynthia ricini und Bombyx mori wurde in verschiedenen Lösungsmitteln bei 45-75°C unter Verwendung Zahlricher wäßriger Salzlösungen als Katalysatoren untersucht. Die auftretenden Salzeffekte werden hauptsächlich der Katalysatoren untersucht. Die auftretenden Salzeffekte werden hauptsächlich der Nucleophilie der Anionen und der Acidität der Kationen zugeschrieben. Substituenteneffekte der Epoxyverbindungen auf die Additionsreaktionen wurden mit Hilfe der modifizierten Taft-Gleichung untersucht.
    Notes: The heterogeneous addition reaction of various monoepoxy compounds with some kinds of silk fibroins e.g. of Dictyoploca japonica, Antheraea pernyi, Philosamia cynthia ricini and Bombyx mori was investigated in various solvents at 45-75°C using aqueous solutions of many kinds of salts as padding catalysts. The salt effects on these reactions of silk fibroins with epoxy compounds were described mainly by the nucleophilicity of the anions and also by the acidity of the cations. The substituent effects of the epoxy compounds on the addition reactions were elucidated by the modified Taft's equation. By means of the solubility parameter of the solvents we were able to explain the solvent dependency of the weight gains of the silk fibroins. The reactivity difference among these silk fibroins was partly described by the variation of shape and the amino acid compositions of the fibers.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 177 (1976), S. 1301-1329 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Salzeffekte sowie Lösungsmittel- und Substitutenteneffekte bei der Reaktion von Cellulose mit Epoxyverbindungen wurden untersucht und mit Literaturangaben verglichen. Der Salzeffekt konnte hauptsächlich mit der Elektronegativität oder der Acidität des Kations sowie mit der Nucleophilie oder der Basizität des Anions beschrieben werden. Die Variation der Reaktion mit den Lösungsmitteln der Epoxyverbindungen konnte auf deren Löslichkeitsparameter zurückgeführt werden. Der Substituenteneffekt der Epoxyverbindungen bei dieser Additionsreaktion wurde mit Hilfe der modifizierten Gleichung von Taft, (logk-logk0)/σ*=(Qp-QsEs)/σ*, ermittelt. Unter dem Gesichtspunkt der neuen Ergebnisse wurde der Reaktionsmechanismus diskutiert.
    Notes: Effects of salts, solvents, and substituents on the reaction of cellulose with epoxy compounds were re-investigated and compared with the published data. The salt effect could be described mainly by the electronegativity or the acidity of the cations, and also by the nucleophilicity or the basicity of the anions. The variation of the reaction with solvents for epoxy compounds could be explained by the solubility parameter of the solvents. The substituent effect of the epoxy compounds on this addition reaction was elucidated by the modified Taft's equation, (logk-logk0)/σ*=(Qp-QsEs)/σ*. The mechanism for the reaction was discussed in the light of the reinvestigated phenomena.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 178 (1977), S. 3253-3256 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Ein neuer thermotroper flüssig-kristalliner Vinyläther, 4-(2-Vinyloxyäthoxy)benzoesäure (1a), wurde durch Hydrolyse des entsprechenden Methylesters 1b erhalten. Seine radikalische Polymerisation in Substanz wurde bei 130-195°C in fester, mesomorpher und isotrop-flüssiger Phase mit 2,2′-Azoisobutyronitril durchgeführt, um den Effekt der Monomerordnung auf die Polymerisationsgeschwindigkeit und die Eigenschaften des Polymers zu untersuchen. Das Auftreten mesomorpher Phasen scheint nicht von einem besonderen Effekt auf die Polymerisationsgeschwindigkeit und den Staudinger-Index begleitet zu sein. Die Geschwindigkeit nahm mit steigender Temperatur zu, d.h. mit abnehmender Ordnung oder erhöhter Beweglichkeit des Monomers. In N,N-Dimethylformamid beträgt der Staudinger-Index bei 30°C 0,06-0,10 dl g-1. Hochkristalline Polymere wurden in der festen und mesomorphen Phase erhalten. Das in der isotrop-flüssigen Phase gebildete Polymer war dagegen weniger kristallin.
    Notes: A new thermotropic liquid crystalline vinyl ether, 4-(2-vinyloxyethoxy)benzoic acid (1a), was obtained by hydrolysis of the corresponding methyl ester 1b. The radical bulk polymerization of this acid was carried out at 130-195°C in the solid, the mesomorphic, and the isotropic liquid phases with 2,2′-azoisobutyronitrile to study the effect of monomer ordering on polymerization rate and polymer properties. No significant effect on the rate of polymerization and the intrinsic viscosity of the products appeared to be associated with the existence of the mesomorphic phases. The rate increased with increasing temperature, i.e., decreasing ordering or enhanced mobility of the monomer. The intrinsic viscosity was 0,06-0,10 dl g-1 in N,N-dimethylformamide at 30°C. High crystalline polymers were obtained in the solid and the mesomorphic phases, whereas the polymer formed in the isotropic liquid phase was a less crystalline solid.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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